<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        body {
            width: 2000px;
            height: 1100px;
        }
        * {
            margin: 0;
            padding: 0;
        }

        #div {
            width: 500px;
            height: 500px;
            border: 1px solid red;
            margin-left: 40%;
            position: relative;
        }
        #div1 {
            width: 40px;
            height: 40px;
            background-color: #2aabd2;
            position: absolute;
            left:100px;
            top:100px;
        }

        #div2 {
            width: 50px;
            height: 50px;
            background-color: #f0ad4e;
        }
    </style>
</head>
<body>
    <div id="div">
        <div id="div1">qq</div>
        <div id="div2">ss</div>
    </div>
<div>aa</div>
</body>
</html>